<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Node</title>
  </head>
  <body>
    <div id="app">
      <div class="houdunren" data="hd">houdunren.com</div>
      <div class="hdcms">hdcms.com</div>
      <div class="xiangjun"><!-- 向军大叔 --></div>
    </div>
    <script>
      const node = document.querySelector(`#app`)
      console.log(node.nodeType) //1
      console.log(node.firstChild.nodeType) //3

      const xj = document.querySelector('.xiangjun')
      console.log(xj.childNodes[0].nodeType) //8
    </script>
  </body>
</html>
